Contains information gathered about the current node.
Syntax
Example
.NET
// This example shows how to allow browsing for an OPC Data Access node by placing a browsing control on the form.
using OpcLabs.EasyOpc.Forms.Browsing;
using System;
using System.Windows.Forms;
using OpcLabs.BaseLib;
namespace FormsDocExamples._OpcBrowseControl
{
public partial class UsageForm : Form
{
public UsageForm()
{
InitializeComponent();
}
private void getOutputsButton_Click(object sender, EventArgs e)
{
// Obtain the current node element.
OpcBrowseNodeElement currentNodeElement = opcBrowseControl1.Outputs.CurrentNodeElement;
// Display the present parts of the current node element in the outputs text text box.
outputsTextBox.Text = "";
if (!(currentNodeElement.ComputerElement is null))
outputsTextBox.Text += $"{nameof(OpcBrowseNodeElement.ComputerElement)}: {currentNodeElement.ComputerElement}\r\n";
if (!(currentNodeElement.ServerElement is null))
outputsTextBox.Text += $"{nameof(OpcBrowseNodeElement.ServerElement)}: {currentNodeElement.ServerElement}\r\n";
if (!(currentNodeElement.DANodeElement is null))
outputsTextBox.Text += $"{nameof(OpcBrowseNodeElement.DANodeElement)}: {currentNodeElement.DANodeElement}\r\n";
}
private void opcBrowseControl1_BrowseFailure(object sender, FailureEventArgs e)
{
// Append the event name and its arguments to the browsing events text box.
browsingEventsTextBox.Text += $"{nameof(OpcBrowseControl.BrowseFailure)}: {e}\r\n";
}
private void opcBrowseControl1_CurrentNodeChanged(object sender, EventArgs e)
{
// Append the event name and the current node element to the browsing events text box.
browsingEventsTextBox.Text += $"{nameof(OpcBrowseControl.CurrentNodeChanged)}; {opcBrowseControl1.Outputs.CurrentNodeElement}\r\n";
}
private void opcBrowseControl1_NodeDoubleClick(object sender, EventArgs e)
{
// Append the event name to the browsing events text box.
browsingEventsTextBox.Text += $"{nameof(OpcBrowseControl.NodeDoubleClick)}\r\n";
}
private void opcBrowseControl1_SelectionChanged(object sender, EventArgs e)
{
// Append the event name to the browsing events text box.
browsingEventsTextBox.Text += $"{nameof(OpcBrowseControl.SelectionChanged)}\r\n";
}
private void setInputsButton_Click(object sender, EventArgs e)
{
// Set the current node to a pre-defined OPC DA item on our server.
opcBrowseControl1.InputsOutputs.CurrentNodeDescriptor.ServerDescriptor = "OPCLabs.KitServer.2";
opcBrowseControl1.InputsOutputs.CurrentNodeDescriptor.DANodeDescriptor = "Demo.Ramp";
}
}
}
namespace FormsDocExamples._OpcBrowseControl
{
partial class UsageForm
{
/// <summary>
/// Required designer variable.
/// </summary>
private System.ComponentModel.IContainer components = null;
/// <summary>
/// Clean up any resources being used.
/// </summary>
/// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
protected override void Dispose(bool disposing)
{
if (disposing && (components != null))
{
components.Dispose();
}
base.Dispose(disposing);
}
#region Windows Form Designer generated code
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
this.opcBrowseControl1 = new OpcLabs.EasyOpc.Forms.Browsing.OpcBrowseControl();
this.setInputsButton = new System.Windows.Forms.Button();
this.getOutputsButton = new System.Windows.Forms.Button();
this.label1 = new System.Windows.Forms.Label();
this.browsingEventsTextBox = new System.Windows.Forms.TextBox();
this.outputsTextBox = new System.Windows.Forms.TextBox();
((System.ComponentModel.ISupportInitialize)(this.opcBrowseControl1)).BeginInit();
this.SuspendLayout();
//
// opcBrowseControl1
//
this.opcBrowseControl1.Location = new System.Drawing.Point(13, 42);
this.opcBrowseControl1.MinimumSize = new System.Drawing.Size(135, 150);
this.opcBrowseControl1.Name = "opcBrowseControl1";
this.opcBrowseControl1.Size = new System.Drawing.Size(450, 300);
this.opcBrowseControl1.TabIndex = 0;
this.opcBrowseControl1.BrowseFailure += new OpcLabs.BaseLib.FailureEventHandler(this.opcBrowseControl1_BrowseFailure);
this.opcBrowseControl1.CurrentNodeChanged += new System.EventHandler(this.opcBrowseControl1_CurrentNodeChanged);
this.opcBrowseControl1.NodeDoubleClick += new System.EventHandler(this.opcBrowseControl1_NodeDoubleClick);
this.opcBrowseControl1.SelectionChanged += new System.EventHandler(this.opcBrowseControl1_SelectionChanged);
//
// setInputsButton
//
this.setInputsButton.Location = new System.Drawing.Point(13, 13);
this.setInputsButton.Name = "setInputsButton";
this.setInputsButton.Size = new System.Drawing.Size(75, 23);
this.setInputsButton.TabIndex = 1;
this.setInputsButton.Text = "&Set inputs";
this.setInputsButton.UseVisualStyleBackColor = true;
this.setInputsButton.Click += new System.EventHandler(this.setInputsButton_Click);
//
// getOutputsButton
//
this.getOutputsButton.Location = new System.Drawing.Point(13, 349);
this.getOutputsButton.Name = "getOutputsButton";
this.getOutputsButton.Size = new System.Drawing.Size(75, 23);
this.getOutputsButton.TabIndex = 2;
this.getOutputsButton.Text = "&Get outputs";
this.getOutputsButton.UseVisualStyleBackColor = true;
this.getOutputsButton.Click += new System.EventHandler(this.getOutputsButton_Click);
//
// label1
//
this.label1.AutoSize = true;
this.label1.Location = new System.Drawing.Point(479, 42);
this.label1.Name = "label1";
this.label1.Size = new System.Drawing.Size(88, 13);
this.label1.TabIndex = 3;
this.label1.Text = "Browsing &events:";
//
// browsingEventsTextBox
//
this.browsingEventsTextBox.Location = new System.Drawing.Point(482, 59);
this.browsingEventsTextBox.Multiline = true;
this.browsingEventsTextBox.Name = "browsingEventsTextBox";
this.browsingEventsTextBox.ReadOnly = true;
this.browsingEventsTextBox.ScrollBars = System.Windows.Forms.ScrollBars.Vertical;
this.browsingEventsTextBox.Size = new System.Drawing.Size(482, 283);
this.browsingEventsTextBox.TabIndex = 4;
//
// outputsTextBox
//
this.outputsTextBox.Location = new System.Drawing.Point(13, 379);
this.outputsTextBox.Multiline = true;
this.outputsTextBox.Name = "outputsTextBox";
this.outputsTextBox.ReadOnly = true;
this.outputsTextBox.Size = new System.Drawing.Size(951, 68);
this.outputsTextBox.TabIndex = 5;
//
// UsageForm
//
this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
this.ClientSize = new System.Drawing.Size(976, 450);
this.Controls.Add(this.outputsTextBox);
this.Controls.Add(this.browsingEventsTextBox);
this.Controls.Add(this.label1);
this.Controls.Add(this.getOutputsButton);
this.Controls.Add(this.setInputsButton);
this.Controls.Add(this.opcBrowseControl1);
this.Name = "UsageForm";
this.Text = "Usage";
((System.ComponentModel.ISupportInitialize)(this.opcBrowseControl1)).EndInit();
this.ResumeLayout(false);
this.PerformLayout();
}
#endregion
private OpcLabs.EasyOpc.Forms.Browsing.OpcBrowseControl opcBrowseControl1;
private System.Windows.Forms.Button setInputsButton;
private System.Windows.Forms.Button getOutputsButton;
private System.Windows.Forms.Label label1;
private System.Windows.Forms.TextBox browsingEventsTextBox;
private System.Windows.Forms.TextBox outputsTextBox;
}
}
Requirements
Target Platforms: .NET Framework: Windows 10 (selected versions), Windows 11 (selected versions), Windows Server 2016, Windows Server 2022; .NET: Linux, macOS, Microsoft Windows
See Also